#include <stdio.h>

void sw(int *,int *);

int main(void)
{
    int a = 0;
    int b = 5;
    sw(&b,&a);
    printf("a = %d\n",a);
    printf("b = %d\n",b);
    return 0;
}

void sw(int *input,int *output)
{
    int temp = 0;
    temp = *input;
    *input = *output;
    *output = temp;
}
